US 12,491,586 B2
Welded joint
Masahiro Matsuba, Tokyo (JP); Takuya Mitsunobu, Tokyo (JP); Masaaki Uranaka, Tokyo (JP); and Toyomitsu Nakamura, Tokyo (JP)
Assigned to NIPPON STEEL CORPORATION, Tokyo (JP)
Appl. No. 18/725,477
Filed by NIPPON STEEL CORPORATION, Tokyo (JP)
PCT Filed Jan. 26, 2023, PCT No. PCT/JP2023/002440
§ 371(c)(1), (2) Date Jun. 28, 2024,
PCT Pub. No. WO2023/145823, PCT Pub. Date Aug. 3, 2023.
Claims priority of application No. 2022-013461 (JP), filed on Jan. 31, 2022.
Prior Publication US 2025/0065450 A1, Feb. 27, 2025
Int. Cl. B23K 35/30 (2006.01); B23K 9/23 (2006.01); B23K 26/322 (2014.01); B23K 35/28 (2006.01); B23K 103/04 (2006.01); B23K 103/16 (2006.01)
CPC B23K 35/3073 (2013.01) [B23K 9/23 (2013.01); B23K 26/322 (2013.01); B23K 35/288 (2013.01); B23K 2103/04 (2018.08); B23K 2103/166 (2018.08)] 7 Claims
OG exemplary drawing
 
1. A welded joint in which a first steel sheet and a second steel sheet are welded by arc welding or laser welding, the welded joint comprising:
the first steel sheet and the second steel sheet; and
a weld bead zone formed by the arc welding or laser welding, wherein
when a zone, which is not affected by heat due to the welding, is defined as a non-heat-affected zone in the first steel sheet and the second steel sheet, at least one of the first steel sheet or the second steel sheet has a plating layer located on at least part of a surface of a base iron and an oxide layer located on the plating layer in the non-heat-affected zone, the plating layer contains: by mass %,
Al: 1.00 to 80.00%;
Mg: 1.00 to 20.00%;
Fe: 0.01 to 15.00%;
Si: 0 to 10.00%;
Ca: 0 to 4.00%, and further selectively contains 0 to 5.000% in total of:
Sb: 0 to 0.500%;
Pb: 0 to 0.500%;
Cu: 0 to 1.000%;
Sn: 0 to 1.000%;
In: 0 to 1.000%;
Bi: 0 to 1.000%;
Ti: 0 to 1.000%;
Cr: 0 to 1.000%;
Nb: 0 to 1.000%;
Zr: 0 to 1.000%;
Ni: 0 to 1.000%;
Mn: 0 to 1.000%;
V: 0 to 1.000%;
Mo: 0 to 1.000%;
Ag: 0 to 1.000%;
Li: 0 to 1.000%;
La: 0 to 0.500%;
Ce: 0 to 0.500%;
B: 0 to 0.500%;
Y: 0 to 0.500%;
Sr: 0 to 0.500%, with the balance composed of 5.00 mass % or more Zn and impurities, wherein
the oxide layer contains a total of 50 mass % or more of one or more of Zn oxide, Mg oxide, and Al oxide,
the weld bead zone has a weld metal and a slag layer formed on part of a surface of the weld metal, and
when Al and Mg are detected elements in the slag layer, the slag layer comprising multiple oxides of Al and Mg, the slag layer contains, by mass %:
Al: 1.0 to 45.0% and
Mg: 1.0 to 30.0%
with the balance composed of Fe, easily oxidizable metallic elements, and impurities.